1. Field of the Invention
The present invention relates generally to magnetic data storage apparatus in which data is magnetically recorded on to a flexible storage medium normally stored in cassettes or cartridges, and more particularly to a novel tape cartridge and associated drive and record/playback apparatus having particular application in the storage and utilization of large quantities of digital data.
2. Description of the Prior Art
Heretofore, high density storage of digital data on a flexible medium has involved the use of both tape media stored in cartridges or cassettes, with the associated drive and record/playback mechanisms either recording (1) on tracts which run the length of the tape, normally referred to as the streaming or streamer technique, or (2) on tracts disposed at angles relative to the length of the tape, normally recorded by helical heads in a manner similar to the technique used in video recorders, or (3) on groups of short length tracts recorded on discreet lengths of the tape, normally accomplished by selectively positioning a length of tape around a rotating head such that the head records a short longitudinally directed tract each time is stopped laterally relative to the length of the tape. This technique is generally referred to as direct access recording.
Among the problems associated with prior art systems are the following: if a cassette form of tape media package is required, the cassette must be unreasonably large in order to accomodate both storage and take-up reels used in the operation thereof. If the chosen storage form is that of a single reel cartridge, there are substantial problems associated with the feeding of the loose tape end through the drive and record/playback apparatus. The primary problem associated with disk type storage formats are that the disks are obviously limited in terms of the quantity of data that can be stored on a single disk.
Another problem associated with the use of tapes as a high volume storage media is that prior art systems have required the use of expensive and frequently complex tape tensioning control mechanisms in order to maintain accurate compliance with the recording and playback heads.
Still another disadvantage of prior art tape drives is that the record and playback heads are unreasonably expensive and formed a major cost component of the drive apparatus.